* {
    margin: 0;
    padding: 0;
    box-sizing: border-box;
}

body {
    font-family: 'Arial', sans-serif;
    line-height: 1.6;
    color: #333;
    background-color: #f4f4f4;
}

.container {
    max-width: 1200px;
    margin: 0 auto;
    padding: 20px;
}

.header {
    background: linear-gradient(135deg, #667eea 0%, #764ba2 100%);
    color: white;
    padding: 2rem 0;
    text-align: center;
    margin-bottom: 2rem;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
}

.header h1 {
    font-size: 2.5rem;
    margin-bottom: 0.5rem;
}

.header p {
    font-size: 1.2rem;
    opacity: 0.9;
}

.feature-grid {
    display: grid;
    grid-template-columns: repeat(auto-fit, minmax(300px, 1fr));
    gap: 2rem;
    margin: 2rem 0;
}

.feature-card {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    text-align: center;
    transition: transform 0.3s ease, box-shadow 0.3s ease;
    cursor: pointer;
}

.feature-card:hover {
    transform: translateY(-5px);
    box-shadow: 0 8px 15px rgba(0, 0, 0, 0.2);
}

.feature-card h3 {
    color: #667eea;
    margin-bottom: 1rem;
    font-size: 1.5rem;
}

.feature-card p {
    color: #666;
    margin-bottom: 1.5rem;
}

.btn {
    display: inline-block;
    background: #667eea;
    color: white;
    padding: 0.8rem 1.5rem;
    border: none;
    border-radius: 5px;
    text-decoration: none;
    font-weight: bold;
    transition: background 0.3s ease;
}

.btn:hover {
    background: #764ba2;
}

.upload-area {
    border: 2px dashed #667eea;
    border-radius: 10px;
    padding: 3rem;
    text-align: center;
    margin: 2rem 0;
    background: #f8f9fa;
}

.upload-area:hover {
    background: #e9ecef;
}

.result-area {
    background: white;
    padding: 2rem;
    border-radius: 10px;
    box-shadow: 0 4px 6px rgba(0, 0, 0, 0.1);
    margin-top: 2rem;
}

.loading {
    display: none;
    text-align: center;
    padding: 2rem;
}

.spinner {
    border: 4px solid #f3f3f3;
    border-top: 4px solid #667eea;
    border-radius: 50%;
    width: 40px;
    height: 40px;
    animation: spin 2s linear infinite;
    margin: 0 auto 1rem;
}

@keyframes spin {
    0% { transform: rotate(0deg); }
    100% { transform: rotate(360deg); }
}

.nav-bar {
    background: white;
    padding: 1rem 0;
    margin-bottom: 2rem;
    border-radius: 10px;
    box-shadow: 0 2px 4px rgba(0, 0, 0, 0.1);
}

.nav-bar ul {
    list-style: none;
    display: flex;
    justify-content: center;
    gap: 2rem;
}

.nav-bar a {
    text-decoration: none;
    color: #333;
    font-weight: bold;
    padding: 0.5rem 1rem;
    border-radius: 5px;
    transition: background 0.3s ease;
}

.nav-bar a:hover {
    background: #667eea;
    color: white;
}